Italian rider Mauro Santambrogio is facing a possible lifetime ban from the sport after failing a second test for a banned substance.

The 30 year old was subjected to an out of competition doping control on October 22, resulting in an A sample finding for testosterone. The UCI announced that finding on Thursday and said that Santambrogio had the right to request and attend the analysis of the B sample.

He has been provisionally suspended in the meantime.

The latest news has stunned many in the sport, given that he was still serving a doping ban for an EPO positive detected on stage one of the 2013 Giro d’Italia.

The then-Vini Fantini rider had been enjoying arguably his best season to date, winning the GP Industria and Artigianato di Larciano, as well as netting second in the Giro del Trentino, third in the Trofeo Laigueglia and scoring top seven finishes in the Gran Premio Città di Camaiore, the Tour de San Luis and Tirreno-Adriatico.

The upsurge in form after a quieter three years at the BMC Racing Team put him on the UCI’s radar and his Giro test on day one was apparently a random control.

He went on to win the 14th stage of the race and finish ninth overall, but lost those results when the positive test became known.

Facing a two year ban, Santambrogio cooperated with investigators and was handed a reduced suspension.

He was eligible to return to competition in November, but his testosterone positive days before that point have almost certainly brought to an end any comeback.